A wide variety of techniques for interfacing passengers with suitable elevators are known in the art. One class of devices call an elevator to a floor to pick up a passenger. This class of devices may be as simple as the well-known up/down call buttons. More recent call destination systems might display a large number of floor buttons or might consist of ten key destination floor call devices. Still other devices include card readers as well as hand-held call devices and smart badges which operate in a wireless fashion, such as using electromagnetic radiation (RF, IR), to indicate the desire to be picked up on a certain floor, the desired destination floor, and possibly the security access for the destination floor.
To inform passengers which elevators will serve them, the technique might be as simple as up/down directional lanterns which light as an elevator approaches a floor, or which light immediately (or fairly soon) after a call is placed. For remote call devices and certain of the destination call devices, an indication may appear on the device itself, such indication typically comprising a letter indicative of the elevator which will respond to that call.
During morning rush hour, up peak elevator traffic may be handled without any call devices in the simplest of techniques, passengers simply walking in and observing on a panel above the elevator the floor numbers of the group of floors being served by any particular elevator which is, or is about to be, standing at the landing. An example of such a system is disclosed in U.S. Pat. No. 4,804,069, entitled “Contiguous Floor Channeling Elevator Dispatching”. The problem with these devices is that they can only be observed within a relatively small area in the immediate vicinity of each elevator, so passengers must hunt for the elevator assigned to a group of floors that includes the destination floor of the passenger. This tends to cause milling around and confusion, which is counterproductive to a smooth upflow of passengers.
A preferred manner of handling morning rush hour, up peak elevator traffic is sometimes referred to as “channeling”, as is disclosed in the aforementioned U.S. Pat. No. 4,804,069 and in U.S. Pat. No. 4,846,311, entitled “Optimized ‘Up-Peak’ Elevator Channeling System with Predicted Traffic Volume Equalized Sector Assignments”. Therein, during the morning rush, floors are assigned to various groupings called “sectors”. In the latter case, the assignment of floors to sectors is altered as the predicted volume of traffic to particular floors changes, in small time intervals (every few minutes), so that a floor may be served with the floors above it on one trip and be served with the floors below it on the next trip. Furthermore, although a given sector, for instance the highest sector in the building, may be relatively stable so that the person on the highest floor can depend upon it being the highest sector, nonetheless that sector may be assigned to a different elevator each time the trip is made. Assigning sectors to different elevators is one of the ways that traffic flow is increased. This of course makes it more difficult for passengers to determine which elevator to take.
In systems having destination call panels, it has been known to provide, typically by means of a letter, the indication of the elevator, which is to serve a group of floors including the floor of the destination, which has just been entered on the call device. However, the use of the destination call device itself slows down the flow of rush hour traffic, and the letters do not themselves provide the best correlation, particularly in view of the fact that the building tenants must remember the letter from some place in a corridor well in advance of the elevator lobby, and typically being a different letter every day.
In PCT publication WO 01/79101, a sector including a passenger's destination floor is identified with a color, and the elevator serving that floor at that time is identified with the same color, in a manner, which is readily observed from any entrance to or any position within a corresponding elevator lobby.
Although color assignment to sectors is a very effective way to serve up-peak traffic during morning rush hour for persons who are able to see colors, it is of no use to persons who are significantly vision-impaired. Use of symbols (such as alphabetic letters) will accommodate persons who have sight but are color blind; however, symbols will not accommodate those who are essentially un-sighted.